Water resistant watch case



July 19, 1966 J. SIMON ETAL 3,261,159

WATER RESISTANT WATCH CASE Filed Sept. 29, 1964 United States Patent 3,261,159 WATER RESISTANT WATCH CASE John Simon, Tramelan, and Josef Gunzinger, Welschenroln', Switzerland, assignors to Gunzinger Freres S.A. Fabrique Technos, Welschenrohr, Switzerland, :1 firm Filed Sept. 29, 1964, Ser; No. 400,133 Claims priority, application Switzerland, Sept. 30, 1963, 11,989/ 63 1 Claim. (Cl. 58-90) The realization of water-resistance in the joint between the glass and the body of the case has always been a difficult problem in the making of water-resistant watch cases; numerous solutions have been proposed which in general have not been satisfactory, especially when complete Water-resistance is necessary such as e.g. in watches for divers.

It has already been suggested to press the rim of the glass against a packing of the body by means of a bezel screwed against a ring-shaped projecting ledge of the latter and to recover this bezel by a false bezel fixed to the same projecting ledge. But as usual the body of the watch case in the inside of the projecting ledge in question is not level and in general needs a rim surrounding the dial to hold in place the packing.

The projecting ledge in question must be fitted to the body of the case after a thread has been cut into it; but when the screwing has been done to the end it proves that on intimate contact between the projecting ledge and the body of the watch case is not guaranteed. In other watch cases Where the projecting ledge is part of the case the thread for the bezel to be screwed on is on the outside of the projecting ledge. It is, however, not possible to cut a snap into this face for the mounting of the false bezel itself. This decreases the usefulness of this false bezel which is to prevent an accidental screwing off of the bezel.

The invention described hereinafter avoids these disadvantages. This is achieved by making the ring-shaped projecting ledge in one piece with the body of the watch case and by cutting the thread for the bezel on the inner side of the latter. The upper surface of the body of the watch case placed inside of said projecting ledge is made plane and has a circular groove for fitting the packing or sealing ring. Because of this plane upper surface the said inner side of the bezel is easily accessible for tools, so that one can cut the thread on the inner side of the projecting ledge. The outer surface is free to be used as mounting surface for the false bezel.

The above and further objects and novel features of the invention will appear more fully from the following description when the same is read in connection with the accompanying drawings. I

FIGURE 1 shows an axial sectional view of an embodiment.

FIGURES 2 and 3 show two other embodiments.

The embodiment of a watch case according to FIG- URE 1 comprises a back cover, and a middle (or the middle part of the case), made in one piece 1, a crystal 2,

3,261,159 Patented July 19, 1966 "ice the watch movement 3, and the dial 4. The body 1 of the case has a projecting ledge 5, integral therewith. On the inner side of this the thread 5a is cut while the outer face has a snap 5b.

The upper surface 6 of the case body placed inside of the projecting ledge 5 is plane and has a circular groove 7. A packing or sealing ring 8 is lodged inside said groove. Owing to this arrangement is is possbile to bring upon the thread on the inner side of the projecting ledge 5. Because this forms one piece with the body of the case it is furthermore possible to tighten the bezel by screwing it very tightly to the projecting ledge without having to fear that the projecting ledge be separated or loosened from the case body. The false bezel 9 which is fitted onto the outer surface of the projecting ledge 5 is kept in place by the snap 5b protects the bezel 10 and prevents that the bezel is accidentally screwed off.

In the embodiment of FIGURE 2 the packing or sealing ring 8a is lodged in a groove inserted in the rim of the crystal.

In the embodiment in FIGURE 3 the packing 8b is partly lodged in a groove 7b inserted on the plane surface of the bezel and partly in corresponding groove on the rim of the crystal. It is further provided with a ring of reinforcement 11 surrounding the rim of the crystal.

What We claim is:

In combination in a Water resistant watch case assembly:

(A) a case body having upper and lower surfaces;

(B) a ring-shaped projecting ledge having inner and outer faces integral with said case body and having threads on said inner face and a snap on said outer face;

(C) a circular groove in the said upper surface of said case body said groove being disposed inwardly of said ledge;

(D) a sealing ring within said groove;

(E) a crystal having lower extermities fitting over said ring flush with said upper surface of said case body;

(F) a bezel screwed in said threads for securing said crystal to said case body; and

(G) a false bezel fitted over said outer face of said ledge and over said bezel; said false bezel being maintained in place by said snap on said outer face.

References Cited by the Examiner FOREIGN PATENTS 1,147,385 11/1957 France.

157,385 12/ 1932 Switzerland. 220,798 7/ 1942 Switzerland. 241,958 8/ 1946 Switzerland.

RICHARD B. WILKINSON, Primary Examiner.

' LEO SMILOW, Examiner.

G. F. BAKER, Assistant Examiner. 

